It is advantageous to apply labels of plastic film material to such containers. For example, plastic film such as polypropylene, polyethylene, polyvinyl chloride and polyethylene-polypropylene laminates are waterproof and present a better appearance more nearly resembling lithograph labels than paper labels.
However plastic labels are difficult to apply properly to the chimes and other circumferential grooves. If heat is applied by an oven to shrink the plastic into the grooves the heating equipment is bulky and costly to build and is expensive to operate. Moreover the results have not been favorable. For example the plastic film material shrinks in the transverse direction, i.e. in a direction perpendicular to the line of flow of the containers through a labeling machine.